How to Clean Bathroom Tile and Grout

Quick answer

Most discoloured grout is soap scum and mildew sitting on the surface, not permanent staining. A soft brush, a mildly alkaline cleaner and a few minutes of dwell time lift the majority of it. Baking soda paste handles moderate build-up; oxygen bleach is the step up for grey or blackened lines. The real fix is prevention — squeegeeing the walls and running the fan after every shower does more than any deep clean, because grout is porous and stays damp long after the tile looks dry.

Key takeaways

  • Grout is porous. It holds moisture and soap residue, so it darkens before the tile does.
  • Dwell time does more work than pressure — let the cleaner sit before scrubbing.
  • Use a soft nylon brush. Wire brushes and abrasive pads erode grout and scratch glaze.
  • Never use vinegar or acidic cleaners on natural stone, marble or unsealed grout.
  • If grout is crumbling or missing, cleaning won't fix it — it needs regrouting.

Why grout gets dirty

Tile is glazed and non-absorbent. Grout, unless it is epoxy or freshly sealed, is not. Every shower leaves a thin film of soap, body oils and hard-water minerals across the walls; that film settles into the grout lines and stays damp, and mildew grows on top of it. That is what turns lines grey, orange or black.

It matters for how you clean. You are usually removing a layer sitting on the grout rather than bleaching the grout itself — which is why a cleaner needs time to soften the film, and why scrubbing harder rarely helps.

The weekly clean

Five minutes once a week beats an hour once a season.

  • Spray the walls while the room is still warm and damp after a shower — residue softens far more easily than when dried hard.
  • Leave it three to five minutes, then wipe with a microfibre cloth and rinse.
  • Squeegee the walls and glass, and leave the door or curtain open.

The squeegee step is the one people skip and the one that matters most. Removing standing water is what stops the cycle restarting the next day.

Deep-cleaning discoloured grout

Baking soda paste. Mix baking soda with a little water and a drop of dish soap. Work it into the lines with an old toothbrush, leave ten minutes, scrub gently and rinse. This handles most soap scum.

Oxygen bleach. Sodium percarbonate in warm water, left fifteen to twenty minutes, then scrubbed and rinsed. Gentler on grout and colour than chlorine bleach, and usually the step that brings grey lines back.

Chlorine bleach, diluted, as a last resort. It lifts dark mildew stains but degrades grout over time and marks coloured grout and some sealants. Ventilate the room, and never mix it with any other cleaner — bleach combined with acids or ammonia produces toxic gas.

Work one small section at a time so nothing dries on the wall before you rinse.

What not to use

Vinegar and lemon cleaners are widely recommended and are fine on glazed ceramic — but they etch marble, travertine and limestone, and slowly break down unsealed cement grout. If you don't know what your tile is, assume it needs a pH-neutral cleaner. Skip steel wool, melamine foam on glossy tile and anything labelled scouring; they dull glaze and open up the grout so it absorbs dirt faster next time.

Cleaning around fixtures and mounts

Anything stuck to the wall creates an edge where water sits. Wipe around and underneath shelves, hooks and holders rather than just over the top, and dry the seam. Adhesive mounts hold fine through normal cleaning, but don't blast the edges with hot water or scrub the seal with a stiff brush — you will work the adhesive loose over time. Our guide on mounting things on tile without drilling covers which surfaces hold.

What we recommend

The equipment list here is short: a squeegee, a soft grout brush, a microfibre cloth and one decent cleaner. Nothing we sell will clean your bathroom, and we would rather say so.

What we do sell is for the other part of the routine. The BathBeats shower phone holder is an adhesive wall mount for tile, glass and mirrors with a Bluetooth speaker built in, so a podcast makes the weekly wipe-down less tedious. It is rated IPX6 — built for shower spray and steam, not submersion, and never for a bath or a pool. It fits 4" to 6.8" screens, and thick or rugged cases have to come off.

It is not the right choice if your walls are textured tile, natural stone or mosaic with grout lines every few centimetres — adhesive needs a flat, smooth area to grip. Use a glass panel or mirror instead, or skip it.

Frequently asked questions

Why does grout go black in one corner only?

That corner stays wet longest — usually the lowest point or the spot furthest from the fan. It is mildew, and it returns until the drying improves.

Does a steam cleaner work on grout?

It lifts surface grime well with no chemicals, but can drive moisture into old grout and loosen failing sections. Be cautious on anything already crumbling.

Should I seal my grout?

Sealing cement grout makes it far less absorbent and is worth doing after a deep clean. It needs redoing periodically.

Can I use bleach on coloured grout?

Not if you want it to stay that colour. Use oxygen bleach instead.

How often should I deep clean?

With daily squeegeeing and ventilation, a couple of times a year. Without that, expect monthly.

Related guides

Last updated 20 September 2026. Nycora is a small independent shop in Vilnius, Lithuania.

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